In recent years, the population of advanced-aged persons has increased. Further, care for solitary advance-aged persons have been socially required. Therefore, use of human body detecting devices have increased as life sensors for seeing whether solitary advanced-aged people live daily lives in good health.
One prior art human body detecting device is an infrared sensor, which detects differences between extreme infrared radiation energies radiated from backgrounds such as indoor walls, floors, and ceilings or the like, and extreme infrared radiation energies radiated from a human body, so as to output a detection signal. Such infrared sensors are mainly utilized for prevention of crimes, and control of indoor illuminations and a ventilation fans.
In addition, another one employs a television camera, for prevention of crimes. This system reproduces a video signal from a television camera, that is positioned in an area to be monitored, on a monitor in a monitoring place; so as to monitor the area. Since a human body detecting device employing a television camera enables a user to see with his eyes, the area to be monitored as it is, the device has an advantage that a direction of the television camera is facilitated.
The above-described prior art human body detecting devices have the following problems.
At first, an infrared sensor type human body detecting device detects a radiated energy fluctuation amount, i.e., a change in a heat quantity, which results in a difficulty in directing the same to the area to be monitored. Next, it is constructed such that a detection signal is output during a predetermined period when an action of the human body is detected. Therefore, when a human body comes to a standstill after it has been detected, and such a standstill state continues beyond a predetermined period, the device fails to output a detection signal. More particularly, the detection state has come to be in an abnormal state, and therefore, the person in the standstill state cannot be detected.
Further, in a human body detecting device employing a television camera, the area to be monitored can be seen with eyes as it is, which results in a difficulty in adapting such a device to a place where a privacy should be respected.
Further, in order to protect a privacy, it might be considered to superimpose noise into the video signal so as to make the video difficult to be seen on a caregiver side. However it is impossible to provide a detailed video information to the caregiver when a caregiven person has fallen into an abnormal state.
Further, from the view of a protecting privacy, as described in Japanese Published Patent No. Hei. 10-234030, it might be considered that an original image captured by the television camera is transmitted from the caregiven person side to the caregiver side, and when the original image is analyzed on the caregiver side, and a predetermined state can be met, the original image is output on the monitor television provided on the caregiver side. However, in this method, the original image is always transmitted to the caregiver side. As such, a device provided on the caregiver side can be intentionally altered so as to output the original image on the monitor television. Further, since an analyzing means for the original image is provided to the caregiver, the original image should be regularly transmitted from the caregiven person's house to the caregiver's house via a public circuit network or the like, which results in requiring a large amount of communication expenses.
The present invention is made to solve the above-described problems. It is an object of the invention to provide a human body detecting device which can be adapted to a place where privacy is respected, such as a toilet or a bathroom, and can be used as a life sensor for seeing whether a person is in good health, and can provide more detailed video information to the caregiver at a distant place when detecting abnormalities in the human body.